Shoe making machine



May 19, 1970 Y H. s. CARR, sR

SHOE MAKING MACHINE 5 Sheets-Sheet 1 Filed April 24, 1968 INVENTOR.

.wwlvvvgy May 19, 1970 I H. s. CARR, SR 3,512,197

' I SHOE MAKING MACHINE Filed April 24, 1968 I s Sheets-Sheet '2 Z g? $74 010 $2 729 Jk May 1 9,. 197 3 Hbs. CARR, SR

SHOE MAKING MACHINE 3 Sheets-Sheet 5 Filed April 24, 1968 H WNN United States Patent 3,512,197 SHOE MAKING MACHINE Harold S. Carr, Sr., Hermitage, Tenn. (2819 Lebanon Road, Nashville, Tenn. 37214) Filed Apr. 24, 1968, Ser. No. 723,697 Int. Cl. A43d 89/00 US. Cl. 124.2 4 Claims ABSTRACT OF THE DISCLOSURE A shoemaking machine including upper and lower membranes adapted to receive a lasted shoe therebetween with the peripheries of the membranes in air-tight sealing engagement, and means for evacuating the air between the membranes so that the membranes adhere tightly around the exterior surface of the shoe.

BACKGROUND OF THE INVENTION This invention relates to a shoemaking machine, and more particularly to a shoemaking machine which will perform the functions of several prior shoemaking machines in a more rapid and efiicient manner.

The art of shoemaking involves many different steps, most of which are preformed independently by separate machines, or manual process. For example, separate machines, or manual processes, are employed for the different steps of forming the upper to the last, securing the counter to the heel portion of the upper, securing the box toe to the inner toe portion of the upper, securing different portions of the upper to the insole, securing the outside to the insole and the upper, conditioning the upper, and heat-setting the upper. I

Furthermore, the manufacture of shoes requires long periods of time, considerable space, expensive and numerous shoemaking machines, and large inventories of in-process materials for heat treating the shoes in order to condition the uppers and develop the appropriate shape in the shoes. The conditioning and shaping of a single shoe can take from a matter of days to several weeks under conventional processes of shoemaking.

SUMMARY OF THE INVENTION It is therefore an object of this invention to overcome most of the above disadvantages in the shoemaking industry by providing a machine which Will combine several of the shoemaking steps.

One object of this invention is to provide a single shoemaking machine which will combine the steps of unitizing the counter and box toe to the upper, condition the upper, heat-set the upper to conform precisely to the shape of the last, and attach the sole to the upper and the insole in a matter of seconds.

Another object of this invention is to provide a shoemaking machine which can perform the steps of unitizing, conditioning, heat-setting and sole-attaching, and with slight modification, can perform the preliminary steps of lasting and securing the upper to the insole.

Another object of the invention is to provide a shoemaking machine which will eliminate 2-4 conventional lasting machines, depending upon the type of shoe construction and the types of lasting machines employed.

A further object of the invention is to provide a shoemaking machine, which in combination with other shoemaking steps, will produce a shoe having a superior shape in almost perfect conformity to the shape of the last.

Another object of this invention is to provide a shoemaking machine which will eliminate the necessity for several costly shoemaking machines and labor, will eliminate a substantial amount of capital invested in in-process merchandise, will eliminate excessive space requirements 3,512,197 Patented May 19, 1970 "ice for the processing of shoes, and will eliminate the cumbersome and time-consuming, conventional heat-setting processes which tend to dry out the shoe while attempting to heat-set the upper to the last.

Another object of this invention is to provide a shoemaking machine which will combine several steps in the shoemaking process and complete the combined steps in a matter of seconds as opposed to the days and weeks consumed under prior known methods of shoemaking.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a shoemaking machine made in accordance with this invention showing a lasted shoe with a detached outsole supported on the lower membrane, and the upper membrane in an open position;

FIG. 2 is an enlarged sectional elevation of the machine disclosed in FIG. 1 with the upper and lower membranes in closed position and the upper and lower membranes conforming to the shoe last under the application of vacuum and heat;

FIG. 3 is a side sectional elevation of a modification of the invention with the shoe last-mounted in upside-down position and the upper membrane in an elevated, inoperative position; and

FIG. 4 is a section taken along the line 44 of FIG. 3 with the membranes in closed, operative position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIGS. 1 and 2 in more detail, the shoemaking machine 10 includes a cabinet 11 having a table top 12 supporting a lower housing 13.

Mounted in the lower housing 13 is an open, rectangular membrane supporting frame .15, to which is detachably fixed a lower membrane attaching frame 16. The lower attaching frame 16 is disclosed as channel-shaped and adapted to receive an angular shaped wedge piece 18.

The lower membrane is preferably a flexible, pliable and somewhat elastic, sheet material, such as rubber, of generally rectangular shape, the edges of which are stretched over and into the channel-shaped frame 16 and held in position by the wedge piece 18, as disclosed in FIG. 2. The wedge piece 18 is held in position relative to the periphery of the membrane 20 and the attaching frame 16 by the head of each bolt 21 which secures the lower leg of the channel frame 16 to the lower supporting frame 15.

As noted in FIGS. 1 and 2, the lower membrane 20 has sufficient thickness and body and is held in a sufficiently taut position that it will support a last 24 and shoe 25.

An upper housing 27 is pivotally connected to the lower housing 13 by hinges 28. Mounted in the bottom portion of the upper housing 27 is an open, rectangular upper membrane supporting frame 30 carrying an upper membrane attaching frame 31 identical in construction to the lower membrane attaching frame 16, except upside down. The lower membrane attaching frame 31 is also channel-shaped for receiving an angular wedge piece 33.

Sealed between the attaching frame 31 and Wedge piece 33 is the periphery of a substantially rectangular upper membrane 35. The upper membrane 35 is made of the same material having the same qualities as the lower membrane 20. However, as best disclosed in FIG. 1, the upper membrane 35 may have a centrally disposed, loose pocket area 36 to accommodate the upper protruding portion of the shoe last 24 when the upper housing 27 is in closed position as disclosed in FIG. 2.

The upper wedge piece 33 is held in position by the heads of the upper bolts 38 which secure the attaching frame 31 to the upper membrane supporting frame 30,

in the identical manner as the lower bolts 21 secure the lower attaching frame 16 to the lower supporting frame 15.

The shapes of the lower membrane attaching frame 16 and the upper membrane attaching frame 31 are preferably identical and congruent so that they will register and carry the corresponding peripheries of the lower membrane and the upper membrane 35 in a completely air-tight sealing engagement when the upper housing 27 is moved to closed position against the lower housing 13, as disclosed in FIG. 2.

The upper housing 27 is held in closed position by latching mechanism disclosed in FIGS. 1 and 2, the details of which are not material to this invention and therefore are not described in detail. The latching mechanism 40 also includes a handle 41 for raising and lowering the upper housing 27 and for manipulating the latching mechanism 40.

An air outlet 43 is formed through the lower membrane 20 perferably in an area which extends laterally beyond any portion of the lower membrane 20 engaging the lasted shoe 25, or the auxiliary sole plate 45. Because of the location of the air outlet 43, the passage of air through the outlet 43 will not be obstructed by anything. except the upper membrane 35, when all the air is exhausted from between the upper and lower membranes 35 and 20. However, in order to eliminate any preliminary obstruction by the upper membrane 35, elongated grooves or channels 46 may be formed in the upper surface of the lower membrane 20 to permit the passage of air from a plurality of areas remote from the air outlet 43, even when the portion of the upper membrane 35 opposing the outlet 43 engages the portions of the lower membrane 20 adjacent the outlet 43.

Connected at one end to the air outlet 43 is an exhaust conduit or hose 47 including a valve 48. The other end of conduit 47 is connected to a vacuum pump 49 mounted within the cabinet 11. The valve 48 may be actuated by a push-button 50 which may be automatically depressed by a flange 51 depending from handle 41 when lowered to latched position. Thus, when the upper housing 27 is completely closed and latched, the valve 48 is automatically opened to immediately exhaust the space between the membranes 35 and 20.

Mounted beneath the lower membrane frame 15 is a horizontal heat shield plate 53 including a plurality of apertures 54. Mounted below the heat shield plate 53 is a heating element 55 supplied with electricity through the electrical conduit 56 from any desired source of electrical energy, not shown. In a similar manner, a heating element 57 is mounted within the upper housing 27 spaced above upper membrane 35 in either operative or inoperative position. The upper heating element 57 is supplied with electricity through the lead 58 from any source of electrical energy, not shown.

Also mounted within the cabinet 11 is a blower or fan 69, preferably including a heating element, to supply forced hot air through a hot air inlet pipe 61 and inlet 62 in the table top 12 into the space confined bythe lower housing 13. The hot air entering through the inlet 62 will follow the direction of the arrows disclosed in FIG. 2 and rise through the apertures 54 in the heat shield plate 53, after picking up additional heat from heating element 55. The hot air then passes across all portions of the outer surface of the lower membrane 20 and then rises around the outer edges of the lower membrane supporting frame 15, the upper membrane supporting frame 30 and across the outer surface of the upper membrane 35. The heat lost from the forced air in the upper housing 27 is restored by the heating element 57. The air is then discharged through the outlet pipe 64 to return to the hot air blower 60.

The heat shield plate 53 may also function as a support to limit the downward movement of the lower membrane 20, and also to prevent the lower membrane 20 from touching the lower heating element 55.

If desired, the upper housing 27 may be provided with a light bulb 66 for illuminating the interior of the upper housing 27, and a glass-covered window 67 in the top of the housing 27 for observation of the interior of the housing 27 in closed position.

In the operation of the machine 10, the upper housing 27 is raised to its open position disclosed in FIG. 1. T he sole plate 45 is placed upon the lower membrane 20 at substantially the center thereof, for certain types of shoes. The sole plate 45 has a periphery extending laterally beyond the periphery of the outsole 76 to be applied to the lasted shoe 25. The sole plate 45 is used to eliminate or reduce the wrap of the lower membrane 20 up around or against the periphery of the outsole 70 when vacuum is created between the membranes 20 and 35. Furthermore, the shape of the sole can be controlled by employing sole plates 45 of different materials and/or thicknesses in order to vary the stiffness or rigidity of the sole plate 45 and therefore the degree of wrap of the lower membrane 26 about the outsole 70.

After the sole plate 45 is positioned on the lower membrane 20, then the lasted shoe 25 and outsole 70 are placed upon the sole plate 45. The lasted shoe 25 includes the upper which has been formed about the last 24 and secured to the insole on the bottom of the last, not shown.

Whether the sole plate 45 is employed or not, care must be taken not to cover the air outlet 43.

After the sole plate 45, outer sole 70 and lasted shoe 25 have been properly, and preferably centrally, positioned on the lower membrane 20, the upper housing 27 is lowered to the closed position, disclosed in FIG. 2, and the handle 41 swung to cause the latching mechanism 40 to securely latch the upper housing 27 to the lower housing 13. As disclosed in FIG. 2, when the latching 27 housing 13. As disclosed in FIG. 2, when the latching mechanism 40 is latched, the valve actuator flange 51 will push the valve button 50 to open the suction valve 48 causing the suction pump 49 to draw air through the exhaust conduit 47 and air outlet 43 from the vacuum sealed spaced between the upper membrane 35 and the lower membrane 20.

In the preferred form of the invention, a vacuum is created between the membranes 35 and 20 in the range of 28.029.5 inches of mercury. The creation of this rather strong vacuum permits the atmospheric pressure to force the lower membrane 20 up flush against the bottom of the sole plate 45. The atmospheric pressure also forces the upper membrane 35 snugly against the upper surface of the auxiliary sole plate 45, the outer periphery of the outsole 70, the outer surface of the upper, and the exposed surfaces of the shoe last 24 so that there is almost perfect conformity of the upper to every detail in the outer surface of the last 24, as clearly disclosed in 'FIG. 2. Because of the differential between the atmospheric pressure on the outsides of the membranes 20 and 35 and the vacuum between the membranes, and particularly the pressure differential on opposite surfaces of the upper membrane 35, as well as the uniformity of the applied pressure, the shoe, and particularly the upper, will conform more closely, snugly and smoothly to the shoe last 24 than similar type shoes under currently known processes carried out manually or by currently known machines.

The pressure applied by the atmosphere to the exterior of the membranes 35 and 20 not only shapes the shoe to the last 24, but also unitizes the upper to the counter 72 and box toe 73 (FIG. 2). Prior to placing the lasted shoe 25 upon the lower membrane 20, a thermo-plastic glue or adhesive material is printed on the interior of the heel portion of the upper and also upon the toe portion. The inner surfaces of the counter 72 and box toe 73 are coated to prevent sticking to the last 24. The counter 72 and box toe 73 are then lightly placed in position upon the heel portion and the toe portion of the upper, re-

spectively, before the shoe is lasted. Then, with the lasted shoe 25 in place and the machine in closed position and with vacuum created between the membranes 20 and 35, the atmospheric pressure and heat exerted upon the upper membrane 35 will cause the counter 72 and box toe 73 to adhere to the corresponding portions of the upper.

While pressure is being exerted upon the membranes 35 and 20 by virtue of the vacuum created between the membranes, the hot air blower 60 is actuated either automatically or manually to force hot air through the inlet pipe 61, inlet '62, through the interior of the lower housing 13 upwardly through the apertures 54 in the heat shield plate 53 and past all portions of the outer surface of the lower membrane 20. The hot air then passes across all portions of the upper membrane 35 and is discharged through the hot air return pipe 64 back to the hot air blower 60.

As previously mentioned, heating elements 55 and 57 are provided to restore lost heat to the air circulating through the lower and upper housings 13 and 27. Both the lower membrane 20 and the upper membrane 35 are heated, not only to heat-set the upper but also to condition the material of the upper.

Before the lasted shoe 25 and outsole 70 are introduced into the machine 10, a pressure-sensitive adhesive or glue is applied to the upper surface of the outsole. Then when the pressure and heat are exerted upon the sealed membranes within the machine 10 in operative position, the outsole 70 is firmly affixed to the bottom of the insole and the inturned portions of the upper by both the pressure and the heat applied through the membranes 20 and 35.

The preferred temperature of the ambient air within the upper and lower housings 27 and 13- is preferably about ZOO-250 F. When rubber is used in the membranes 35 and 20, it would melt at these temperatures unless the hot air is circulated. Moreover, the circulation of the hot air permits uniform application of heat to all portions of both membranes 35 and 20, and consequently to all portions of the shoe.

Since the membranes 20 and 35 are impermeable to air, the appearance of the finished shoe is further improved because the shoe, and particularly a leather shoe, can be adequately heated without drying out the leather. The leather shoe, and particularly the shoe upper, will have a better finish because the tanners finishes applied to the leather prior to lasting, will be drawn to the surface without escaping or evaporating.

Not only are all of the above enumerated processes of this invention carried out simultaneously, efficiently and more effectively than corresponding processes have been carried out in the known art of shoemaking, but the processes of this invention require only 3060 seconds or less.

After the operation of the machine 10 is completed, the handle 41 is raised to automatically close the valve 48 and cut off the vacuum between the membranes 20 and 35. Furthermore, the hot air blower 60 and the heating elements 55 and 57 are also de-energized at about the same time that the valve 48 is closed when the handle 41 is raised to unlock the latching mechanism 40. The upper housing 27 is then opened to the position of FIG. 1, and lasted shoe 25 together with its attached sole 70 may be removed for further processing.

FIGS. 3 and 4 disclose a modified form of the invention for carrying out the preliminary steps of lasting the shoe upper and securing the upper to the insole.

The machine '75 includes a table top 76 supporting a lower housing 77. Fixed within the lower housing 77 is a lower membrane supporting frame 78 substantially identical to lower membrane supporting frame of FIG. 2, but with fewer details disclosed in FIG. 3. The supporting frame 78 is preferably open and rectangular and has afiixed thereto by any convenient means, such as bolts, not shown, the periphery of a lower membrane 80, preferably of a flexible, pliable and somewhat elastic sheet material, such as rubber, similar to the lower membrane 20 of FIG. 2. However, in the machine 75, the lower membrane 80 is not a truly rectangular sheet, but is provided with a depending pocket 81 to support a shoe last 83 and shoe upper 84 mounted on the last 83 in upside down position.

In order to stabilize the last 83 and shoe upper 84 in upside down position, a last supporting rod 85 is fixed to the bottom of the lower housing 77 and projects upwardly through a pair of collars or grommets 86 sandwiching the membrane 80 therebetween. The last support rod '85 is adapted to be slidably received through aligned openings in the membrane 80 and collars 8-6, but

sealed in such a manner as to eliminate any air leakage between the rod and the openings, not shown. The upper end of the rod 85 is inserted into a mating opening 87 in the top of the upside down last 83 A toe support rod 89' is also fixed to the bottom of the lower housing 77 and projects upwardly, terminating in an enlarged toe rest 90 for engaging the lower membrane 80 beneath the toe portion of the upper 84.

An air outlet 92 is formed in the lower membrane 80 and communicates with a suction pump, not shown, similar to the suction pump 49 disclosed in FIG. 2, through an air exhaust conduit 93. Here again, care must be taken that the air outlet 92 will not be blocked by those portions of the membrane 80 which might engage the last 83 or the shoe upper 84 before the other portions of the membranes.

The lower housing 77 also includes a heat shield 95 including hot air apertures 96, similar to the hot air shield 53 of FIG. 2. A hot air inlet pipe 97 is connected to inlet 98 extending through the table top 76 and the bottom Wall of the lower housing 77 to communicate with the chamber within the lower housing 77 beneath the hot air shield 95. A lower heating element 99 is mounted beneath the hot air shield 95 to provide auxiliary heat to the hot air introduced through the inlet 98. The lower heating element '99 is supplied with electricity through the lead 100 to a source of electric power, not shown.

The hot air inlet pipe '97 is connected to a hot air blower, not shown, such as the hot air blower 60 disclosed in FIG. 2.

Mounted directly above and in vertical alignment with the lower housing 77 is the upper housing 102 provided at each corner with a vertically depending rod 103 telescopingly and slidably received within a corresponding sleeve 104 mounted at each corresponding corner of the lower housing 77. The bottoms of the rods 103 are fixed to a transverse yoke plate 105, which in turn is fixed to a piston rod 106 for vertical reciprocable movement within a fluid pressure cylinder 107. Thus, by supplying fluid under pressure to either of the fluid hoses 108, the rods 103 move vertically in their respective sleeves 104 to raise the upper housing 102 to its open inoperative position disclosed in FIG. 3, or to its lower closed operative position disclosed in FIG. 4.

The upper housing 102 is provided with an open rectangular membrane supporting frame 109 supporting the periphery of an upper membrane 110. There is sufficient slack in the middle of the upper membrane 110 to provide a pocket portion 111.

The upper membrane frame 109 is identical in size and is congruent to the lower membrane frame 78 and is vertically aligned with the lower frame 78, so that when the upper frame 109 is lowered to its operative position, it will snugly engage the lower frame 78 and provide an air-tight sealed engagement between the outer peripheries of the upper membrane 110 and the lower membrane 80, as disclosed in FIG. 4.

In order to control the collapsing of the upper membrane 110 about the bottom portion of the upside down lasted shoe 84 and the insole, not shown, an elongated top portion of the pocket 111 is fixed between elongated bars 114, which in turn are supported by a U-shaped yoke 115. The horizontal portion or bight 116 of the yoke 115 includes a horizontal slot 17 adapted to receive a horizontally reciprocating pin 118 eccentrically mounted upon a disk 119. The disk 119 is mounted upon a shaft 120 journaled in a bearing 21 fixed to the top of the upper housing 12, and adapted to be rotated by handle 122. The handle 122 is adapted to be manually rotated through only a few degrees of arc, and then locked in position to hold the lift bar 114, and consequently the pocket 111, in a predetermined elevated position.

The purpose of the vertically adjustable pocket 111 is to permit the lower portions of the membrane 110 to be drawn inwardly against the insole of the lasted shoe 84 before the excess upper portion of the pocket 111. The elevation of the pocket 111 may be adjusted for different types and sizes of shoes.

The upper housing 102 also includes upper heating element 125 connected to an electrical lead 126, which conducts electrical energy from a source, not shown, to the element 125. A hot air outlet 127 is formed in the wall of the upper housing 102 and communicates with a hot air return line 128 which communicates with a hot air blower, not shown, similar to the hot air blower disclosed in FIG. 2.

The operation of the machine 75 discloses in FIGS. 3 and 4 is very similar to the machine disclosed in FIGS. 1 and 2. The arrangement of the upper housing 102 to be raised and lowered strictly in a vertical path by the movement of the rods 103 within the sleeves 104, as opposed to the hinged upper housing 27 of FIGS. 1 and 2, is a preferred form of opening and closing either machine 10 or 75. The vertical reciprocable movement of the upper housing 102 relative to the lower housing 77 permits the entire periphery of the upper membrane 110 to move into operative sealing engagement with the entire periphery of the lower membrane 80 simultaneously. Furthermore, the upper membrane supporting frame 109 will engage all portions of the lower support frame 78 so that there will be uniform engagement and equal pressure applied simultaneously to all portions of both frames 78 and 109. On the other hand, it is possible for the pivotal arrangement of the upper housing 27 and lower housing 13 to cause a progressive engagement of the upper membrane 35 with the last 24 and lasted shoe 25 so that wrinkles could conceivably develop in the upper membrane as the upper housing 27 swings in the closed position.

The handle 122 is first manipulated to adjust the lift bars 114 and pocket 111 to the desired elevated position. Then, the fluid cylinder 107 is actuated to lower the housing 102 into engagement with the housing 103 so that the peripheries of the membranes 110 and 80 are completely sealed against leakage of air. The vacuum pump, not shown, and the hot air blower, not shown, are energized to produce the vacuum in a range comparable to that created in the machine 10 to cause the membranes 80 and 110 to be drawn inwardly and in close engagement with all portions of the last 83 and the lasted upper 84. The hot air circulates through the inlet hose 97, inlet 98, lower housing 77, apertures 96 and around and in contact with the entire exterior surface of the lower membrane 80. The hot air then rises past the peripheries of supporting frames 78 and 109 and circulates through the upper housing 102 to heat the entire exposed outer surface of the upper membrane 110. The air is then discharged through the outlet 127 and return line 128.

The primary purpose of the machine 75 is to tightly, smoothly and uniformly shape the upper 84 to the last 83 and to Wrap the bottom portions of the upper 84 around the bottom of the last 83 into adhesive engagement with the insole, not shown, to which a thermo-plastic adhesive has been applied.

For smaller size shoes lasted in machine 75, a solidinsert may be required, preferably located against the heel of the upper, in order to occupy the excess space between the lasted shoe and the interior surfaces of the membranes 110 and 80.

Where both machines and 10 are used, the total time required for heat-setting the shoe may be divided, so that the shoe is partially heat-set while being lasted in machine 75, and the balance of the heat-setting is completed in machine 10.

It is also within the scope of this invention to incorporate a single upper and lower housing with one set of membrane supporting frames, with interchangeable membranes of different fiexibilities, shapes and with different size pockets or no pockets at all, for carrying out the entire operations described above in connection with both machines 10 and 75. In other words, a single machine with single membrane supporting frames and interchangeable membranes could be employed to carry out the preliminary steps of lasting, and the subsequent simultaneous steps of conditioning, unitizing, heat-setting and sole attaching.

Either of the above machines 10 or 75 may be used for processing any kind of footwear except canvas, rainwear, or extruded types of footwear.

It is a material advantage to the operation of this invention, as embodied in machines 10* and 75, that the membranes are squeezed or forced against the lasted shoe by a pressure differential between the inner and outer surfaces of the membranes created by a vacuum between the membranes, as opposed to pressure greater than atmospheric pressure applied to the exterior membrane surfaces. The application of exterior ressure requires closed, thick-walled, chambers around the membranes, plus expensive air pressure generating equipment and controls. Furthermore, the circulation of hot air and the application of heat, and particularly electric heat, within a pressurized chamber would further increase the exterior pressure, necessitating additional controls, and might create a dangerous explosive mixture within the chamber.

What is claimed is:

1. A shoemaking machine comprising:

(a) a lower membrane impermeable to air, having a periphery,

(b) a lower open frame fixed to said periphery to provide a suspended shoe last covering area in said lower membrane,

(c) an upper membrane impermeable to air, having a periphery,

(d) an upper open frame fixed to the periphery of said upper membrane to provide a suspended shoe last covering area in said upper membrane,

(e) means for relatively moving said upper and lower frames toward each other to a closed position in which the peripheries of said membranes engage each other in a continuous, air-tight seal, and for relatively moving said frames away from each other to an open position in which a shoe last may be introduced between said membranes,

(f) said membranes being made of a uniform, flexible material capable of conforming to the exterior detailed surface of the shoe material carried by said last,

(g) at least one of said membranes being sufiiciently slack that a shoe last may be received between said membranes when said frames are in closed position, without undue tension being exerted upon either of said membranes,

(h) an air outlet in one of said membranes,

(i) vacuum means connected to said air outlet for 9 10 reducing the air pressure between said membranes in prising means adjustably supporting the central portion of closed position; said upper membrane in vertical spaced relationship to (j) means providing air communication between said said upper frame.

outlet and the last of the shoe between said membranes, even when said membranes are completely 5 References Cited drawn together and against said shoe, and (k) means uniformly heating said membranes in closed UNITED STATES PATENTS position. 2,489,643 11/1949 Hunter 12-1 X 2. The invention according to claim 1 in which Said 2,651,062 9/1953 Smiley 12-1 heating means comprises means for circulating hot fluid 2,654,901 10/1953 M i 12 1 across and in contact with the exterior surfaces of said 10 2 771 519 11 195 t t 12 1 membranes.

3. The invention according to claim 1 further compris- PATRICK D. LAWSON, Primary Examiner ing auxiliary means for supporting a shoe last upside 7 down on said lower membrane. 15 US. Cl. X.R.

4. The invention according to claim 3 further com- 12-1 

